On Jan 28, 6:50 am, Antoon Pardon <[EMAIL PROTECTED]> wrote: > My personal preference would be that python would allow people the > choice, with the default being that any operation that resulted > in a non numeric result would throw an exception. > > People who somehow made it clear they know how to work with inf, and > NaN results, would get silent NaN where no exceptions would be thrown.
I also think this would be the ideal situation. Getting there would require a lot of thought, planning, a PEP or two, and some hard work and tricky coding to deal with all the different ways that the C compiler, libm and hardware might try to mess things up. Right now I don't have time for this :-( Anyone else? > > Putting aside sorting and max/min, what is the use-case for having > > comparisons with NaN succeed? What benefit will it give you? > > I guess the same benefit it gives to those that have operations with > NaN succeed. If 3 * NaN should succeed and all sort of other stuff, > why suddenly make an exception for 3 < NaN. Right. This is especially true when the result of the comparison is treated as number (i.e. 0 or 1) rather than as a boolean, and goes back into the calculation in some way. On the other hand, there are certainly situations where you want a comparison with a NaN to raise an exception. I guess this is why IEEE-754r provides two sets of comparison operators: signaling and non-signaling. Mark -- http://mail.python.org/mailman/listinfo/python-list